Add that fourth tile...
... And then, instead of tile area, which is a rather unpleasing melancholic focus, hows about sides, or corners?! Then each tile (assuming you have regular people tiles :P) has within it a factor of 4. or, focus on both! Then you have 80 (a factor of 4) tiles, each with *4* sides, each with *4* corners... Then they only need to have an area or a dimension which is a factor of 4 and you have 4 factors of 4 within your tiles!
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Mon 7 Jun 2010, 22:22,
archived)